A Real-world Study of Immunotherapy Combination Regimens for Treating Liver Cancer in Cold Regions

Hepatocellular carcinoma (HCC) is a common global malignancy. In China, the disease burden is substantial: HCC ranks fifth in cancer incidence and third in mortality, with a 5-year relative survival of only 14.4%. In Northeast China's cold regions, metabolic diseases such as hypertension, hyperlipidemia, and diabetes are prevalent and may influence HCC prognosis. Recently, PD-1/PD-L1 inhibitor-based combination regimens (with targeted therapy, chemotherapy, or locoregional treatment) have achieved major breakthroughs, significantly extending overall and progression-free survival. These regimens have become the first-line backbone for unresectable HCC. Investigating their real-world effectiveness and safety is critical for optimizing regional treatment strategies.

Inclusion Criteria 1. Patients with a clinically confirmed diagnosis of primary hepatocellular carcinoma, intrahepatic cholangiocarcinoma, or combined hepatocellular-cholangiocarcinoma, with measurable tumor lesions. 2. Patients who have long-term residence in the cold regions of Northeast China, specifically in provinces with an annual mean temperature between 1.6°C and 10°C: Heilongjiang Province, Jilin Province, and selected cities in Liaoning Province. 3. Patients who have received an immune-based therapy regimen. 4. Patients with complete clinical data who meet the enrollment criteria, retrospectively collected from January 1, 2020, to December 31, 2025. Exclusion Criteria 1. Patients with concurrent other malignancies. 2. Patients who are confirmed pregnant or breastfeeding. 3. Any other conditions that, in the investigator's judgment, make the patient unsuitable for participation in this study.